1. Field of the Invention
The present invention relates to a fluid apparatus such as a wobble-type fluid apparatus and a swash-plate fluid apparatus, which is suitably used for a compressor in a vapor compression refrigerant cycle for a vehicle.
2. Description of Related Art
A wobble-type fluid apparatus (e.g., swing-swash plate compressor) includes a rotary member, a swing member and a rotation lock mechanism. The rotary member has a swash surface slanted relative to a shaft of the fluid apparatus, and rotates integrally with the shaft. The swing member is connected to the swash surface through a thrust bearing, and swings with the rotation of the rotary member, thereby reciprocating a piston of the fluid apparatus. The rotation lock mechanism is disposed to prevent the swing member from rotating together with the rotary member.
JP-A-63-94085 proposes a swing support mechanism used as the rotation lock mechanism. Specifically, in JP-A-63-94085, a bevel gear provided on the rotary member is engaged with a bevel gear provided on the swing member, thereby constructing the swing support mechanism. The swing support member supports the swing member in capable of swing. Therefore, when the fluid apparatus such as the compressor is operated, noise is readily generated due to gear collision between the bevel gears.
On the other hand, in JP-A-2-275070, the swing member is supported by a spherical slide surface of a slide member, thereby reducing the noise due to the gear collision. However, when the shaft rotates at a high rotational speed, the swing member swings and vibrates while rotating about the shaft. The vibration from the swing member is transmitted to a housing of the compressor, thereby causing large sound noise. Furthermore, at this time, the slide member and its support portion slide at a high rotational speed, thereby reducing reliability (durability) of the compressor.
Further, since the swing member has an unsymmetrical shape due to the rotation lock portion disposed on the swing member, a moment is structurally applied to the swing member so as to increase or decrease its slant angle with respect to the shaft. As a result, in a variable displacement compressor for controlling its displacement by changing the slant angle of the swing member, the displacement (i.e., slant angle) becomes unstable, thereby inducing oscillation due to hunting.